Sodium diethyldithiocarbamate

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Partition coefficient type:

octanol-water

Key result

Type:

log Pow

Partition coefficient:

<= -1.1

Temp.:

20 °C

pH:

>= 7 - <= 9

Details on results:

The experimental determination of the partition coefficient of Sodium diethyldithiocarbamate could not be conducted according to OECD test guidelines 107 and 117 as they are not applicable to this test item. To fulfil the requirements of the OECD test guidelines, the partition coefficient of a test item should be determined using the test item in its undissociated (neutral) form. Furthermore, the test item has to be stable in water and octanol during the test period.

The test item Sodium diethyldithiocarbamate is a salt which dissociates in water.

The OECD test guideline 117 (HPLC Method) could not be performed because the test item Sodium diethyldithiocarbamate hydrolyses too rapidly into carbon disulfide and a-n- diethylamine and therefore the distribution behaviour of the parent substance could not be determined.

Nevertheless the determination of the partition coefficient was performed as preliminary test according to OECD test guidelines 107 (Shake Flask Method) using UV-VIS spectroscopy as detection method.

It was possible to distinguish between the test item and free carbon disulfide in the octanol phase by using UV-VIS detection.

Therefore, only the results of the preliminary tests are reported. This is obviously in line with the common expectation that ionisable substances remain preferably in the aqueous phase.

The partition coefficient of the test item was found to be: log Pow = < - 1.1

Additionally the partition coefficient was calculated for Sodium diethyldithiocarbamate applying the software KOWWIN v1.67 owned by the U.S. Environmental Protection Agency.
The partition coefficient of the test item was: log Pow = - 1.4 (calculated as non-dissociated sodium component)

No data on pH are available; however, based on the experiments with structurally related substance sodium dibutyldithiocarbamate and considering the structure of the substance, pH is expected to be in a range 7-9.

Conclusions:

The partition coefficient of the test isubstance was found to be log Pow = < - 1.1 at 20 °C, where the pH is expected to be between 7 and 9

Executive summary:

The conventional determination of the octanol-water partition coefficient (Log Pow) could not be performed following OECD TG 117 (HPLC Method) as the test substance rapidly hydrolysis into carbon disulfide and a n-diethylamine. Since the distribution behaviour of the parent substance could not be determined, the test substance was assessed in its undissociated (neutral) form.
The octanol-water partition coefficient (Log Pow) was performed in a preliminary test according to OECD TG 107 (Shake Flask Method) using UV-VIS spectroscopy. This detection method allowed to distinguish between the test item and free carbon disulfide in the octanol phase. This is obviously in line with the common expectation that ionisable substances remain preferably in the aqueous phase. At 20 °C, the partition coefficient of the test substance was found to be log Pow = < - 1.1, where the pH is expected to be in a range 7 and 9. 
Calculating the partition coefficient by applying the software KOWWIN v1.67 showed a partition coefficient of log Pow = - 1.4 (calculated as non-dissociated sodium component)

Description of key information

log Kow=<-1.1 at 20 ˚C (experimental)
log Kow = -1.4 (calculated with KOWWIN v1.67 as undissociated sodiuem diethyldithiocarbamate)

Key value for chemical safety assessment

Log Kow (Log Pow):

-1.1

at the temperature of:

20 °C

Additional information

Data from a GLP-compliant guideline study, adequate for assessment.